#include<stdio.h>
#include<string.h>
#include<ctype.h>
 
 void reverse_word(char *word){
     int len = strlen(word);
     int start = 0, end = len - l;
     while(start < end){
         char temp = word[start];
         word[start] = word[end];
         word[end] = temp;
         start++;
         end--;
     }
 }
 void decode_message(char *message){
     char *word = strtok(message," ");
     while(word != NULL){
         reverse_word(word);
         printf("%s ", word);
         word = strtok(NULL, " ");
     }
     printf("\n");
     
 }
 int is_valid_input(char *message){
     for(int i = 0; message[i]; i++){
         if(!isalpha(message[i]) && message[i]!=' '){
             return 0;
         }
     }
     return 1;
 }
 int main(){
     char message[101];
     printf("Enter a message: ");
     fgets(message, sizeof(message),stdin);
     message[strcspn(message, "\n")] = 0;
     
     if(!is_valid_input(message)){
         printf("Invalid input\n");
     }else{
         decode_message(message);
     }
     return 0;
     
     
}